This invention relates to a method and means for treating or preventing irritable bowel syndrome with a combination of polymeric substances or materials comprising as essential components an anion-binding polymer and a hydrophilic polymer. Irritable bowel syndrome is a complex of gastrointestinal symptoms manifested by abdominal pain and distention and by altered bowel habits. It is the most common symptom complex encountered by gastroenterologists and may account for 50% of outpatient gastroenterological complaints. There are no known organic causes for the disease, and it is frequently associated with stress and emotional disturbance. Irritable bowel syndrome occurs most frequently in the age group from 20 to 50 years old and occurs two to five times more frequently in females than in males. This painful disease is prevalent in approximately 20% of the adult population of the USA. The consequences of the disease can be socially debilitating and induce severe sexual dysfunction in many patients, especially females. Although not life threatening, irritable bowel syndrome (IBS) is a major health problem from the standpoint of decreased quality of life and reduction of productivity.
There is presently no effective treatment for irritable bowel syndrome (K. B. Klein, Controlled treatment trials in the irritable bowel syndrome: a critique, Gastroenterology 95: 232-241, 1988). Although largely ineffective, current treatment is multifactorial and consists of stress management, diet, and drugs, in that order. The patient is reassured that the disease is not life threatening and is advised to reduce or eliminate any controllable stress in his or her life. Relaxation exercises and biofeedback may be attempted to alter the psychogenic components of the illness. With respect to diet, the patient is advised to avoid any food to which he or she possesses a known sensitivity with respect to exacerbating the problem. A high fiber diet, either insoluble wheat bran or soluble psyllium, is almost routinely recommended, but with little if any positive benefit (Dietary fiber, food intolerance, and irritable bowel syndrome, Nutrition Reviews 48: 343-346, 1990).
Numerous drugs have been tried for the treatment of irritable bowel syndrome, but none has demonstrated sufficient efficacy to be of practical benefit to most patients. Psychoactive drugs, such as anxiolytics and antidepressants, even if effective for a given patient, have very limited, short-term utility because of the high potential for addiction to and abuse of these agents. Antispasmodics and various antidiarrheal preparations have been used but, even if they are effective, long-term treatment is precluded by problems such as development of tolerance, toxicity, or abuse potential. Several excellent reviews examine in detail the symptomology, diagnosis, and treatment of irritable bowel syndrome. These include: W. L. Hasler and C. Owyang, Irritable bowel syndrome, In: Textbook of Gastroenterology, Ed. by T. Yamada, J. B. Lippincott Company, Philadelphia, Pa., 1696-1714 (1991); M. M. Schuster, Irritable bowel syndrome, In: Gastrointestinal Disease, Pathophysiology Diagnosis and Management, Fourth Edition, Ed. by M. H. Sleisenger, J. S. Fordtran, W. B. Saunders Company, Philadelphia, Pa., 1402-1418 (1989); and W. S. Haubrich, Irritable bowel syndrome, Gastroenterology, Fourth Edition, Ed. by J. E. Berk, W. B. Saunders Company, Philadelphia, Pa., 2425-2444 (1985).
Numerous patents have claimed activities of various types represented as being effective for relieving irritable bowel syndrome symptoms. For the most part they relate to substances which possess spasmolytic activity and thereby decrease intestinal motility. U.S. Pat. Nos. 4,611,011, 4,701,457, and 4,745,131 disclose a series of amidinoureas which reduce intestinal motility and are useful for treating irritable bowel syndrome. 1-Azabicyclo[2.2.2]octan-3-yl-2-aryl-3-azacyclo-2-hydroxypropionates and their quaternary salts, which possess antispasmodic activity and are useful for treating irritable bowel syndrome, are disclosed in U.S. Pat. No. 4,843,074. Calcium channel antagonists exhibit muscle relaxing and antispasmodic activities. A series of substituted imidazolyl-alkyl-piperazine and diazepine derivatives, disclosed in U.S. Pat. No. 5,043,447, are calcium channel antagonists and may be useful as antispasmodics for treating irritable bowel syndrome. 2-Aminomethylalkynylalkyl-1,3-dithiane derivatives with calcium-channel blocking activity and potentially similar uses are disclosed in U.S. Pat. No. 4,877,779. A series of triazinone derivatives with spasmolytic activity for treating irritable bowel syndrome are disclosed in U.S. Pat. No. 4,562,188.
In addition to antispasmodic agents, compounds with other activities have been disclosed which may relieve the symptoms of irritable bowel syndrome. U.S. Pat. No. 4,239,768 discloses a series of arylimidazolidinylidene ureas which decrease the sensitivity of the bowel to distension and thereby relieve irritable bowel symptoms. U.S. Pat. No. 4,970,207 discloses a series of benzodiazepine derivatives which are cholecystokinin antagonists and which may be useful for a large number of medical indications which include irritable bowel syndrome.
Since diarrhea is one frequent component of irritable bowel symptomatology, anti-diarrheal agents have been used to treat this disease. Unfortunately, such agents tend to exacerbate the constipatory phase of the disease and are, therefore, of little practical, long-term benefit.
Calcium polycarbophil is a hydrophilic polymeric substance which is sold as an over-the-counter preparation for the relief of irritable bowel syndrome symptoms. A low degree of effectiveness has precluded widespread use of this material by patients suffering from irritable bowel symptoms.
In spite of the many treatments and inventions devised to relieve or prevent irritable bowel syndrome, the unfortunate fact is that presently no suitable long term, safe and efficacious treatment or preventative is available for this troublesome and widespread disease.
To the best of my knowledge, no such combination therapy has been suggested for the treatment of irritable bowel syndrome. Moreover, the only known references which even come close are U.S. Pat. No. 5,102,664, by the present applicant, in which compositions for the control of hypercholesterolemia are disclosed, comprising cholestyramine and pectin together with a seedy fibrous fruit and other materials for effecting the oral acceptability of gritty drugs, most of the components of which composition are unnecessary according to the present invention, and the prior art cited in that patent, as well as a publication by Schwandt, et al. entitled "CHOLESTYRAMINE PLUS PECTIN IN TREATMENT OF PATIENTS WITH FAMILIAL HYPERCHOLESTEROLEMIA", appearing in Atherosclerosis 44, 379-383 (1982), in which granular pectin and cholestyramine were individually administered to patients having hypercholesterolemia in an amount of 28 grams per day for the entirely different purpose of that study.
Accordingly, to the best of my knowledge, no combination of the essential polymers employed according to the method of the invention has ever been employed in any way for the treatment or prevention of irritable bowel syndrome, nor has any pharmaceutical composition consisting essentially of dry powdered admixtures thereof been made available for such purpose.